<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <script type="text/javascript" src="../assets/js/vue.js"></script>
    <title>component-4</title>
</head>
<body>
    <h1>component-4</h1>
    <hr>
    <div id="app">
       <component v-bind:is="who"></component>
       <button @click="changeComponent">changeComponent</button>
    </div>

    <script type="text/javascript">
        var componentA={
            template:`<div style="color:red;">I'm componentA</div>`
        }
        var componentB={
            template:`<div style="color:green;">I'm componentB</div>`
        }
        var componentC={
            template:`<div style="color:pink;">I'm componentC</div>`
        }
       
        var app=new Vue({
            el:'#app',
            data:{
                who:'componentA'
            },
            components:{
                "componentA":componentA,
                "componentB":componentB,
                "componentC":componentC,
            },
            methods:{
                changeComponent:function(){
                    if(this.who=='componentA'){
                        this.who='componentB';
                    }else if(this.who=='componentB'){
                        this.who='componentC';
                    }else{
                        this.who='componentA';
                    }
                }
            }
        })
    </script>
</body>
</html>